ATM it would probably be a .400x.408 Cheytac blank although McGowen has a .402x.409 that looks interesting too. Its only offered in 1-14 or 1-18 and if i went to a 40cal i would probably prefer a 1-16 just so its slow enough for conicals but fast enough for some BH209 sabotless loads. It might be a tad slow for some of the long 300gr 40cals unless you can shoot them faster.
If it was a dedicated 300gr sabotless rifle for BH209 the 1-14 is probably a better choice to insure stability. Most 405wins are 1-13 or 1-14 and shoot a jacketed 300gr upto about 2200fps. From what ive seen sofar thats about what you will get from 120gr BH209 and a 300gr 40cal sabotless.
Last edited by Gm54-120; 05-05-2018 at 09:35 AM.